Various compounds are known which comprise in their molecule a nucleus of the adamantyl type, whose structure with four condensed hexagonal rings produces various particular physical and chemical properties due to its steric rigidity. Derivatives of the azaadamantane or [3,3,1]azatricyclodecane types, with an adamantyl group wherein a nitrogen atom is substituted for a bridgehead carbon atom, at the junction of three of the condensed rings of the tetracyclic adamantyl nucleus, have been studied very little. An example of a method of preparation of such derivatives of the azaadamantane type is described in French Pat. No. 2,358,404.